I have two adams needle that are very big and i have had them for alot of years. They have full sun but never have they flowered. Whats the possible problem with them?
Where they transplanted? http://www.dariasworld.info/photo_yucca_filamentosa.htm Or perhaps it's a matter of watering/rainfall? http://www.flowershopnetwork.com/blog/adams-needle-yucca-isnt-blooming/